/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.jbpm.compiler.xml.processes;

import java.util.HashSet;

import org.jbpm.compiler.xml.Handler;
import org.jbpm.compiler.xml.Parser;
import org.jbpm.compiler.xml.core.BaseAbstractHandler;
import org.jbpm.process.core.ContextContainer;
import org.jbpm.process.core.context.exception.ActionExceptionHandler;
import org.jbpm.process.core.context.exception.ExceptionScope;
import org.jbpm.workflow.core.DroolsAction;
import org.kie.api.definition.process.Process;
import org.w3c.dom.Element;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;

public class ExceptionHandlerHandler extends BaseAbstractHandler implements Handler {

    public ExceptionHandlerHandler() {
        if ((this.validParents == null) && (this.validPeers == null)) {
            this.validParents = new HashSet<Class<?>>();
            this.validParents.add(Process.class);

            this.validPeers = new HashSet<Class<?>>();
            this.validPeers.add(null);

            this.allowNesting = false;
        }
    }

    public Object start(final String uri, final String localName,
            final Attributes attrs, final Parser parser)
            throws SAXException {
        parser.startElementBuilder(localName, attrs);
        return null;
    }

    public Object end(final String uri, final String localName,
            final Parser parser) throws SAXException {
        final Element element = parser.endElementBuilder();
        ContextContainer contextContainer = (ContextContainer) parser.getParent();

        final String type = element.getAttribute("type");
        emptyAttributeCheck(localName, "type", type, parser);

        final String faultName = element.getAttribute("faultName");
        emptyAttributeCheck(localName, "faultName", type, parser);

        final String faultVariable = element.getAttribute("faultVariable");

        ActionExceptionHandler exceptionHandler = null;
        if ("action".equals(type)) {
            exceptionHandler = new ActionExceptionHandler();
            org.w3c.dom.Node xmlNode = element.getFirstChild();
            if (xmlNode instanceof Element) {
                Element actionXml = (Element) xmlNode;

                DroolsAction action = ActionNodeHandler.extractAction(actionXml);
                (exceptionHandler).setAction(action);

            }
        } else {
            throw new SAXParseException("Unknown exception handler type " + type, parser.getLocator());
        }

        if (faultVariable != null && faultVariable.length() > 0) {
            exceptionHandler.setFaultVariable(faultVariable);
        }

        ExceptionScope exceptionScope = (ExceptionScope) contextContainer.getDefaultContext(ExceptionScope.EXCEPTION_SCOPE);
        if (exceptionScope == null) {
            exceptionScope = new ExceptionScope();
            contextContainer.addContext(exceptionScope);
            contextContainer.setDefaultContext(exceptionScope);
        }

        exceptionScope.setExceptionHandler(faultName, exceptionHandler);

        return null;
    }

    public Class<?> generateNodeFor() {
        return null;
    }

}
